U.S. patent number 4,977,377 [Application Number 07/337,709] was granted by the patent office on 1990-12-11 for microwave water cut monitor with temperature controlled test cell.
This patent grant is currently assigned to Texaco Inc.. Invention is credited to Earl L. Dowty, Michael G. Durrett, Gregory J. Hatton, David A. Helms, John D. Marrelli, Joseph D. Stafford, David J. Stavish.
United States Patent |
4,977,377 |
Durrett , et al. |
December 11, 1990 |
Microwave water cut monitor with temperature controlled test
cell
Abstract
A petroleum stream microwave water cut monitor includes test
cell means which contains a reference petroleum multiphase fluid
sample and which has a sample stream of a petroleum stream passing
through it. The test cell is maintained at a predetermined
temperature. A source provides microwave energy to one of a first
pair of antennae which provides the petroleum stream flowing in the
test cell or the reference sample in the test cell with microwave
energy. One of a second pair of antennae receives the microwave
energy that has passed through either the petroleum stream or the
reference sample. A detector detects the received microwave energy
and provides a signal corresponding thereto. An indicator provides
an indication of the water cut of the petroleum stream in
accordance with the received signal power and a phase difference
between the source provided microwave energy and the received
microwave energy.
Inventors: |
Durrett; Michael G. (Houston,
TX), Helms; David A. (Houston, TX), Hatton; Gregory
J. (Houston, TX), Dowty; Earl L. (Katy, TX),
Marrelli; John D. (Houston, TX), Stafford; Joseph D.
(Bellaire, TX), Stavish; David J. (Houston, TX) |
Assignee: |
Texaco Inc. (White Plains,
NY)
|
Family
ID: |
23321680 |
Appl.
No.: |
07/337,709 |
Filed: |
April 13, 1989 |
Current U.S.
Class: |
324/640; 324/606;
324/637; 324/647; 73/61.44 |
Current CPC
Class: |
G01N
22/04 (20130101); G01N 33/2823 (20130101) |
Current International
Class: |
G01N
22/04 (20060101); G01N 33/28 (20060101); G01N
33/26 (20060101); G01N 22/00 (20060101); G01N
022/00 () |
Field of
Search: |
;324/58.5A,58.5R,58A,58R,441,640,641,637,606,647,639 ;73/61.1R |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Eisenzopf; Reinhard J.
Assistant Examiner: Mueller; Robert W.
Attorney, Agent or Firm: Kulason; Robert A. O'Loughlin;
James J. Gillespie; Ronald G.
Claims
What is claimed is:
1. A petroleum stream microwave water cut monitor comprising:
test cell means for containing a reference petroleum multiphase
fluid sample and for having a sample stream of a petroleum stream
flowing through it,
temperature means connected to the test cell means for maintaining
the test cell means at a predetermined temperature,
source means for providing microwave energy,
first antenna means connected to the source means for providing
microwave energy into the petroleum sample stream or the reference
sample,
second antenna means for receiving microwave energy that has passed
through the petroleum sample stream or the reference sample and
providing the received microwave energy as test microwave
energy,
detector means connected to the second antenna means for detecting
the power of the test microwave energy and providing a power signal
corresponding thereto, and
indicator means connected to the second antenna means, to the
source means and to the detector means for providing an indication
of the water cut of the petroleum stream in accordance with the
power signal and the phase difference between the source provided
microwave energy and the received microwave energy; and
in which the test cell means includes:
a body having at least three channels therein for fluid passage and
two channels for microwave energy passage,
fluid source means for providing the reference sample to a first
fluid channel,
sample stream receiving means for receiving the sample stream and
providing it to a second fluid channel,
temperature control fluid receiving means for receiving the
temperature control fluid and providing it to a third fluid
channel,
means for allowing the sample stream and the temperature control
fluid to exit from the body; and
wherein one fluid channel and one microwave channel intersect each
other at right angles and the second fluid channel and the other
microwave channel intersect each other at right angles.
2. A monitor as described in claim 1 in which the indicator means
provides the indication of the water curtain accordance with the
power signal, the phase difference between the source provided
energy and the received microwave energy and the temperature
signal.
3. A monitor as described in claim 2 in which the temperature means
includes:
heat exchanger means connected to the test cell means for providing
a temperature control fluid to and through the test cell means so
as to maintain the test cell means at the predetermined
temperature.
4. A monitor as described in claim 2 in which the temperature means
further includes:
means connected to the heat exchange means and to the test cell
means for returning the temperature control fluid from the test
cell means back to the heat exchange means,
temperature sensing means connected to the heat exchange means for
sensing the temperature of the test cell means and providing a
corresponding temperature signla to the heat exchange means,
and
in which the heat exchange means includes:
means connected to the temperature sensing means and responsive to
the temperature signal for regulating the temperature of the
temperature control fluid.
5. A monitor as described in claim 4 in which each microwave
channel contains a material, except for that portion of the
microwave channel that crosses a fluid channel, that is impervious
to fluids but permits passage of the microwave energy.
6. A monitor as described in claim 5 in which the first antenna
means includes:
first providing antenna means spatially arranged with one of the
microwave channels for providing microwave energy into the one
microwave channel,
second providing antenna means spatially arranged with the other
microwave channel for providing microwave energy into the other
microwave channel, and
first switch means connected to the source means and to the first
and second transmitter antennas for providing the microwave energy
transmitted by the source means to either the first transmitter
antenna means or to the second transmitter antenna means; and
the second antenna means includes:
a first receiving antenna spatially arranged with the one microwave
channel,
a second receiving antenna spatially arranged with the other
microwave channel,
second switching means connected to the first and second receiving
antenna and cooperating with the first switching means for passing
microwave energy that has passed through a fluid and received by a
receiving antenna to the detector means and to the indicator
means.
7. A monitor as described in claim 6 in which the solid material in
the microwave channel is teflon.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to water cut monitors in general and,
more particularly, to microwave water cut monitors.
SUMMARY OF THE INVENTION
A petroleum stream microwave water cut monitor includes test cell
means which contains a reference petroleum multiphase fluid sample
and which has a sample stream of a petroleum stream passing through
it. The test cell is maintained at a predetermined temperature. A
source provides microwave energy to one of a first pair antennae
which provides the petroleum stream flowing in the test cell or the
reference sample in the test cell with microwave energy. One of a
second pair of antennae receives the microwave energy that has
passed through either the petroleum stream or the reference sample.
A detector detects the received microwave energy and provides a
signal corresponding thereto. An indicator provides an indication
of the water cut of the petroleum stream in accordance with the
received signal power and a phase difference between the source
provided microwave energy and the received microwave energy.
The objects and advantages of the invention will appear more fully
hereinafter from a consideration of the detailed description which
follows, taken together with the accompanying drawing wherein one
embodiment of the invention is illustrated by way of example. It is
to be expressly understood, however, that the drawings are for
illustration purposes only and are not to be construed as defining
the limits of the invention.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partial simplified block diagram and a partial
schematic of a microwave water cut monitor constructed in
accordance with the present invention.
FIG. 2 is a simplified block diagram of the test apparatus shown in
FIG. 1.
FIG. 3 is a drawing of the test cell shown in FIG. 2.
FIGS. 4 and 5 are cross-sectional drawings of the test cell shown
in FIG. 3 .
DESCRIPTION OF THE INVENTION
The water cut monitor shown in FIG. 1 includes a microwave
transmitter 3 providing electromagnetic energy, hereinafter
referred to as microwave energy, at a microwave frequency.
Transmitter 3 is low powered and may use a microwave gun source.
Transmitter 3 provides microwave energy to directional coupler 4.
Directional coupler 4 provides microwave energy to a conventional
type voltage controlled phase shifter 5 and to test apparatus 8.
All conductance or carrying of microwave energy is accomplished by
using conventional type waveguides and coaxial cables.
Test apparatus 8 has a line 10, carrying a sample stream of a
multi-phase petroleum stream, entering apparatus 8. The sample
stream leaves test apparatus 8 by way of a line 11. Apparatus 8
will be described in more detail hereinafter. Suffice to say at
this point that microwave energy leaving test apparatus 8 in line
11, hereinafter referred to as test microwave energy, is microwave
energy that is either passed through the sample stream or has
passed through a reference sample. The test microwave energy is
applied to a directional coupler 18. Directional coupler 18
provides the test microwave energy to a detector 22 and to a mixer
28. Detector 22 provides an intensity signal E1 corresponding to
the power of the microwave energy received by antenna 16 or 70 and
hence the intensity of the received microwave energy.
Voltage control phase shifter 5 provides microwave energy,
hereinafter called the reference microwave energy, to mixer 28
which mixes the reference microwave energy and the test microwave
energy to provide two electrical signals E2, E3, representative of
the phases of the reference microwave energy and the test microwave
energy, respectively.
A differential amplifier 30 provides an output signal E0 in
accordance with the difference between signals E2 and E3. Signal E0
is a function of the phase difference between the reference
microwave energy and the test microwave energy and is provided to a
feedback network 34. Feedback network 34 provides a signal C to
voltage control phase shifter 5, controlling the phase of the
reference microwave energy, and to a mini-computer means 40. Signal
E0, and hence signal C, decreases in amplitude until there is
substantially 90.degree. phase difference between the reference
microwave energy and the test microwave energy. Voltage control
phase shifter 5 indicates the amount of phase shift required to
eliminate the phase difference.
Signals E1, T and C are provided to a conventional type
mini-computer means 40 which contains within it memory means having
data related to phase and power for various percentages of water
cuts that could be encountered in the production stream. Phase
Shifter 5 also provides an enable signal to computer means 40
allowing computer means 40 to utilize signals T, C and E1 as
address signals to select the proper water cut value. Computer
means 40 provides signals, corresponding to the selected water cut
value, to readout means 44 which may be either display means or
record means or a combination of the two.
With reference to FIGS. 1 and 2, test apparatus 8 includes a test
cell 53. Test cell 53 will be described more fully hereinafter.
Microwave energy from directional coupler 4 enters switch means 58
which provides microwave to test cell 53 through either a line 62
or a line 64. Line 62 provides the microwave to an antenna 63 which
radiates the microwave energy into the sample stream. Similarly,
when microwave energy is provided by line 64, it is provided to an
antenna 65. Antenna 65 radiates the microwave energy into the
reference sample. Line 66 carries test microwave energy received by
an antenna 67 after it has passed through the sample stream.
Similarly, line 69 carries microwave energy received by an antenna
70 after it has passed through the reference sample. Switch means
72 receives the test microwave energy from either line 66 or line
67 and provides it to directional coupler 18.
A reference sample source 77 provides the reference sample fluid to
test cell 53 by way of a line 80 having a valve 84. A channel in
test cell 53 connects line 80 to another line 88 having a valve 90.
In operation, source 77 provides the reference fluid through test
cell 53. A measurement could be made while it is flowing, or sample
fluid could be contained in a static condition in test cell 53 by
closing valve 90 until the channel within test cell 53 is
completely filled. To drain the reference sample fluid from test
cell 53 valve 84 is closed while valve 90 is opened.
However, the temperature of the sample stream flowing through test
cell 53 is important since variations in temperature will lead to
different readings. The present invention controls the temperature
of the sample stream flowing through test cell 53. In this regard a
pump 95 pumps a fluid heated to a predetermined temperature through
a line 97 to test cell 53 which leaves test cell 53 by way of line
100. The heating fluid is provided to a temperature control means
105 which heats it to the predetermined temperature and provides it
to pump 95. Further, a temperature sensor 108 mounted in test cell
53, senses the temperature of test cell 53 and provides it back to
temperature control means 105 so as to control the temperature of
the heating fluid provided to pump 95.
With reference to FIG. 3, there is shown test cell 53 having
microwave entrance ports 115 and 118. On the other side of test
cell 53 as represented by dash lines are microwave exit ports 125
and 128. Connecting microwave entrance port 115 and microwave exit
port 125 is a microwave channel 130. Similarly a microwave channel
132 connects microwave entrance port 118 with microwave exit port
128.
Also shown in FIG. 3 are fluid channels 136 and 140. Since fluid
channels 136, 140 and 142 are in line in this View of test cell 53
only one set of dash lines represents them. This can seen better in
FIG. 4 which has a cut away view of test cell 53 along the line
4--4 in the direction of the arrows. There is shown a body 145
which may be made of metal having fluid channels 136, 140 and 142
passing through it longitudinally and microwave channels 130 and
132 for the microwave energy cut transversely through it. It should
be noted that channels 130 and 132 are shown as being offset from
each other. However this offset is not necessary to the practice of
the present invention.
It should also be noted that fluid channels 136, 140 have a
rectangular cross-section so that the microwave energy that passes
through the fluids, always has the same distance of passage.
Referring to FIG. 5, there is a view of test cell 53 along the line
5--5 in the direction of shown in FIG. 3. Channel 130 is filled
with a solid material 150, such as high density teflon, that is
conductive to microwave energy, except for that portion of channel
130 that forms a cross-section of fluid channel 136. Cut into body
145 is microwave entrance port 115. Further there is another
chamber 154 which connects microwave entrance port 111 and enters
into material 150 in channel 130. This is for the insertion of
microwave antenna 63, which may be of the commercial type made by
Omni Spectra, Part No. 2057-5134-02. Similarly, microwave exit port
125, for antenna 67, is shown with an additional chamber 155 which
enters into material 150. Again this is for the purpose of
monitoring the sample stream. Basically it is the same type of
antenna as is entered with entrance port 115, but again modified
for the present application. As can be seen, exit port 125 is
longer than entrance port 115. The microwave energy when applied to
the antenna 63 enters material 150 and is directed to cross channel
136 until it reaches the antenna 67 inserted in exit port 125.
Referring also to FIG. 2, lines 10 and 11 are connected in a
conventional manner to channel 136 so that the sample stream in
line 10 will flow through test cell 53 to line 11. Similarly, lines
80 and 88 are connected to fluid channel 140 in such a manner that
the sample fluid in line 80 will enter fluid channel 140 and exit
test cell 53 through line 88. Similarly antenna 67 in entrance port
118 is connected to line 63 and antenna 70 in exit port 128 is
connected to line 67.
As can be seen in FIG. 3, temperature sensor 108 which is a
thermocouple, is inserted into a chamber cut into block 125 and
thus reads the temperature of block 125 as the temperature of the
reference sample and as of the production sample stream.
With reference also to FIGS. 2 and 3, lines 97 and 100 are
connected in a conventional manner to fluid channel 142 so that the
heating fluid flows through channel 142 and heats block 145. A
preferred temperature is the temperature of the sample fluid
entering test cell 53 from line 10 in which case it may be
desirable to also test the temperature of the sample fluid in line
10 and provide a second temperature signal to the temperature
control means. This has not shown in the drawings because the
sample stream temperature may also be determined beforehand and is
substantially constant. In either case the heating of block 125
will not add to the heat of the sample stream unless its
temperature has changed. More important, however, the temperature
of the sample stream as it passes through test cell 53 will be
uniform. The reference sample will also be brought up to the
temperature of the sample stream so that the data gathered from
testing of both the sample stream and the reference sample will
have a greater degree of accuracy.
Although channel 142 is shown as being located between fluid
channels 136 and 140 if pressure is a problem and the strength of
block 125 is suspect, fluid channel 142 may be moved with the idea
in mind that it should generally be equidistant from the sample
stream flowing in fluid channel 136 and the reference sample in
fluid channel 140 so as to keep them at the same temperature.
Basically, the reference sample's power and phase shift is used as
base line data in mini-computer means 40. The base line data and
the test data derived from the petroleum sample stream are
temperature corrected by mini-computer means 40. Mini-computer
means 40 determines the water-cut in accordance with the corrected
base line data, the corrected test data and look-up table stored in
its memory.
* * * * *